An ASTM A351 CF8C Check Valve is a valve made from high alloy steel designed to withstand corrosion from air or chemical mediums. CF8C, equivalent to 347 stainless steel, offers excellent corrosion resistance and has an attractive surface finish. This type of check valve adheres to the execution standard ASTM A743/A744/A351. Check valves, also known as non-return valves, allow fluid flow in only one direction and typically feature two openings: one for entry and one for exit. They come in various types suited for a wide range of applications and are commonly found in household items.